Favorite Spark plugs...

[Vettehead Mikey]

Early-on, it was implied by "Vettehead Mikey," that iridium-tipped spark plugs are hype.
Mikey, Mikey, you've been hit in the head one too many times by those hockey pucks.

True enough on both counts, but I also acknowleged in a later post:

"The high cost plugs do last longer, but most of us will never own or use the car long enough to take advantage of that."

The inference being towards typical useage of an ageing C3 as opposed to a daily driver.

I had a set of iridium plugs in my recently departed Infiniti and they were still as good as new after at least 160,000 kms. I put them back in the car and sold it as is. I assume my new Jag has iridium (or similar) plugs also and further assume that they will last just as long. I'll get back to you in about 10 years to confirm, assuming I can withstand constant pucks to the head.

Regarding the SAE papers you're read, please post the reference numbers. I'll get ahold of a copy through our subscription at work. I'm always willing to learn, particularly when it's from a credible source that has conducted actual A-B tests and where the tests have relevancy to the subject at hand.

 

[80Vette]

Sooooo.....In conclusion?

Aside from the 2 year roll of name-calling, geographical jabs, historical relevance of a religion & personal BS....What WOULD be the best plug for a C-3 era Vette?


I have a 1980 with a 3/4 cam, edelbrock EPS intake & Edelbrock carb, 3inch exhaust to flowmaster 40's...


I need new plugs & wires NOT BS!

It looks like my choices are:
A. the AC Platinums
B. the AC Rapid Fires
C. AC Iridium


HELP!

 

[Evolution1980]

What WOULD be the best plug for a C-3 era Vette?

what is my favorite plug?
The Denso Iridium Power. I have them in all my vehicles...I use the ITF20 in the '71 C3

Anything Hib says I considered to be 100% gospel.

 

[RUSS O'BLENES]

I want opinions on your fav...getting ready for the Cruse-fest and i am thinkin of changing...currently use AC ..350....Have a few mods....Edelbrock carb and intake, headers,electronic ignition....maybe i should stay with these...im sure this has been beat to death but i thought i would ask.
Thanks, Chas

I AM AN ENGINE BUILDER,AND HAVE ALWAYS FOUND THAT I GET MORE RACES FROM AUTOLITE THAN ANY OTHER. JUST MY OPINION. NICE CAR! HAPPY MOTORING. RUSS

 

[RUSS O'BLENES]

If we could keep the discussion to the technical, that would be nice.


Regarding iridium tipped electrodes, my understanding is that the main benefit these confer is no electrode wear, i.e. longer life. In that sense they're similar to platinum tipped electrodes.

If you think about the combustion process I'm really not sure how much difference the brand of plugs used can make. All you're trying to do is generate a spark of sufficient temperature to ignite the mixture. Providing you've got sufficient voltage to ionize the gap and sharp corners on the electrodes for charge concentration, then ignition will happen.

'73

I agree with you 73. I think the major difference is the type of ignition. I have found that the autolite 3911 generally lasts a few more races than the champion C59YC, but I can't say that I have seen any difference in power. As far as fouling, a good MSD will fire just about anything. Happy Motoring. Russ

 

[RUSS O'BLENES]

Technical? Well, do we need a scientific diseration, which I am not capable of. Or, perhaps we could read a few scapes from vendor sites, which sell coppper, platinum and iridium plugs (me wonders why they would manufacture these types of plugs if they are hype - but I digress):

From ACDelco regarding iridium:

"ACDelco, an important player in the 'aftermarket' for the automotive industry, has released a new high-performance spark plug, which uses the platinum group metal iridium.

The ACDelco Professional Iridium Plug is the latest in a range of products the company prides itself on having developed for all types of vehicles, reports Autofan.com.

ACDelco spark plugs product specialist Michelle Glazier said: 'Iridium is one of the strongest, densest precious metals on earth. And with a 100,000-mile limited warranty offered by ACDelco, customers can be confident that these spark plugs are built to last.'

The plugs boast a melting point 700 degree Celsius higher than that of platinum, and are therefore able to burn fuel more efficiently and deliver better performance. They also require less precious metals for the electrodes than platinum-tipped plugs.

'If you look at an iridium tip, it's equivalent to about the size of two pinheads', said Ms Glazier. 'It's less drain on the electrical system because it's smaller, and it's a more efficient use of the energy in your vehicle.'

Specially designed electrodes increase electric field strength and reduce sparking voltage, which results in better cold starting and quick acceleration. They also offer enhanced flame spread during combustion, with a secondary microdischarge on the centre electrode that burns off carbon deposits and ensures improved antifouling performance."

From a European racing website (just in case you are French - Canada you know):

"Because of the properties of Iridium, the spark plugs centre electrode can be made with a much smaller diameter than with platinum types (usually 0.8mm for NGK and 0.7mm for Denso), Gold or gold palladium and copper/nickel types. This means that spark plugs potential difference is more concentrated and hence less 'spark jump' voltage is required - this can be as much as 5,000 volts less than with standard plug types. Ignition is improved and less strain is placed on the ignition system. Benefits of improved ignition/combustion include better fuel economy, increased power/acceleration and especially better throttle response."

But, this is boring....

Yes it is boring. Happy Motoring. Russ

 

[71-84 IMSA Widebody]

CHAMPIONS....racing-C57HCX..........street-NASCAR PLUGS-RC9YC or RC12YC

 

[craig32]

I have a 1980 with a 3/4 cam, edelbrock EPS intake & Edelbrock carb, 3inch exhaust to flowmaster 40's...

What exactly IS a '3/4 cam'? Mine is .531 lift, 290 duration, does that qualify?

BTW, I buy AC, just like the factory put in it.

Craig